Characteristics of extracoronary vascular disease in heart transplant recipient

Abdominal aortic aneurysm in heart transplant recipients: new insights from a 30-year experience at a single center

OBJECTIVE

The improvement in survival rates for heart transplant recipients (HTRs) has increased their risk of developing extracardiac diseases such as abdominal aortic aneurysms (AAAs). The purposes of this study were to evaluate the prevalence and to describe the clinical features and natural history of AAA in HTRs.

METHODS

A retrospective review of all patients (375) who underwent heart transplantation (HT) at our center over a 32-year period (1983-2015) was carried out.

RESULTS

We identified 20 patients (5.3%) with AAA. All but one patient were male (95%), and most of them (80%) had a history of ischemic heart disease (IHD) prior to transplantation. The mean age of the patients with AAA at transplant was 57.2±7.3 years (range: 42-62 years). Seven of the 20 patients with AAA already had an AAA (30 to 55 mm) prior to transplantation. The average aneurysm size at the time of diagnosis was 40.9±9.6 mm, and the average patient age at the time of diagnosis was 62.2±8.3 years. The mean linear expansion rate was 10.6±2.12 mm/y, and the exponential expansion rate was 0.220±0.040 year^-1 respectively. The median follow-up time was 5.4 years (range 0.1-27.4 years). The median survival was 143 months (95% confidence interval (CI) 65 to 180 months) for the 20 HTRs with AAA and 68.8 months (95% CI 46 to 88 months) for the other HTRs.

CONCLUSIONS

The natural history of AAA in HTR is characterized by an increased expansion rate. Male HTR with end-stage IHD are particularly at risk and should be closely followed-up after HT.

National Trends In Kidney, Heart And Liver Transplants Among Patients With And Without Chronic Obstructive Pulmonary Disease In Spain (2001-2015)

Background

To describe trends and outcomes during admission for solid organ transplants, excluding lungs, in people with or without COPD in Spain (2001–2015).

Methods

We used national hospital discharge data to select all hospital admissions for kidney, heart and liver transplants. We estimated admission rates stratified by COPD status. We analyzed the Charlson Comorbidity Index, therapeutic procedures and outcomes.

Results

We identified 52,020 admissions (33,293 for kidney transplant, 3,937 for heart transplant and 14,790 for liver transplant). Patients with COPD accounted for 2.5%, 4.2% and 3.5% of kidney, heart and liver transplant patients, respectively. The number of kidney and liver transplants increased among COPD patients over the study period, whereas the number of heart transplants remained stable. In all cases, COPD patients were significantly older and had more coexisting medical conditions than those without COPD. Among patients who underwent a kidney transplant, there were no significant differences in the clinical characteristics analyzed between the groups, but the overall in-hospital mortality (IHM) rate was significantly higher in COPD patients than in those without COPD (2.22% vs 0.58%, p=0.008). There were no differences for any of the study variables or for the IHM rate in patients who underwent a heart transplant (14.63% in both groups). Among patients who underwent a liver transplant, COPD patients had lower prevalences of infection and complications than those without COPD. The IHM rate was also significantly lower in COPD patients than in non-COPD controls who underwent a liver transplant (4.07% vs 8.91%, p=0.002).

Conclusion

COPD prevalence in patients undergoing renal, heart and liver transplants is lower than it has been described in the general population. However, we did not find differences in the clinical characteristics analyzed between COPD and non-COPD patients. Furthermore, the IHM rate was only higher in COPD patients who underwent a kidney transplant but not in those undergoing a heart or liver transplant.

Ischemic Stroke after Heart Transplantation

Cerebrovascular complications after orthotopic heart transplantation (OHT) are more common in comparison with neurological sequelae subsequent to routine cardiac surgery. Ischemic stroke and transient ischemic attack (TIA) are more common (with an incidence of up to 13%) than intracranial hemorrhage (2.5%). Clinically, ischemic stroke is manifested by the appearance of focal neurologic deficits, although sometimes a stroke may be silent or manifests itself by the appearance of encephalopathy, reflecting a diffuse brain disorder. Ischemic stroke subtypes distribution in perioperative and postoperative period after OHT is very different from classical distribution, with different pathogenic mechanisms. Infact, ischemic stroke may be caused by less common and unusual mechanisms, linked to surgical procedures and to postoperative inflammation, peculiar to this group of patients. However, many strokes (40%) occur without a well-defined etiology (cryptogenic strokes). A silent atrial fibrillation (AF) may play a role in pathogenesis of these strokes and P wave dispersion may represent a predictor of AF. In OHT patients, P wave dispersion correlates with homocysteine plasma levels and hyperhomocysteinemia could play a role in the pathogenesis of these strokes with multiple mechanisms increasing the risk of AF. In conclusion, stroke after heart transplantation represents a complication with considerable impact not only on mortality but also on subsequent poor functional outcome.

Aortic aneurysms and trans-apical endovascular repair in high risk heart transplant recipient, one year follow up

Aortic aneurysms cause major morbidities and mortalities. Operative intervention in ascending aneurysms and dissections is the treatment of choice although there is the risk of major complications because of technical difficulties, late diagnoses, affected hemodynamic and organ mal perfusion. Improved survival of heart transplant (HTx) recipients, acceptance of older donors with co morbidities and advances in HTx give rise to new pathological challenges in the cardiovascular field. Only a few articles have been reported about cardiac and aorta surgery in HTx recipients. Endovascular treatment for aortic pathology in zone 0 is an emerging treatment option. We report the first trans-apical endovascular ascending aorta repair (EVAR) in a 26-year-old HTx recipient, with the history of mediastinitis and lack of femoral access. She had an uneventful operative and post-operative EVAR course.

Interferon-γ-mediated allograft rejection exacerbates cardiovascular disease of hyperlipidemic murine transplant recipients

RATIONALE

Transplantation, the most effective therapy for end-stage organ failure, is markedly limited by early-onset cardiovascular disease (CVD) and premature death of the host. The mechanistic basis of this increased CVD is not fully explained by known risk factors.

OBJECTIVE

To investigate the role of alloimmune responses in promoting CVD of organ transplant recipients.

METHODS AND RESULTS

We established an animal model of graft-exacerbated host CVD by combining murine models of atherosclerosis (apolipoprotein E-deficient recipients on standard diet) and of intra-abdominal graft rejection (heterotopic cardiac transplantation without immunosuppression). CVD was absent in normolipidemic hosts receiving allogeneic grafts and varied in severity among hyperlipidemic grafted hosts according to recipient-donor genetic disparities, most strikingly across an isolated major histocompatibility complex class II antigen barrier. Host disease manifested as increased atherosclerosis of the aorta that also involved the native coronary arteries and new findings of decreased cardiac contractility, ventricular dilatation, and diminished aortic compliance. Exacerbated CVD was accompanied by greater levels of circulating cytokines, especially interferon-γ and other Th1-type cytokines, and showed both systemic and intralesional activation of leukocytes, particularly T-helper cells. Serological neutralization of interferon-γ after allotransplantation prevented graft-related atherosclerosis, cardiomyopathy, and aortic stiffening in the host.

CONCLUSIONS

Our study reveals that sustained activation of the immune system because of chronic allorecognition exacerbates the atherogenic diathesis of hyperlipidemia and results in de novo cardiovascular dysfunction in organ transplant recipients.

Effect of peripheral vascular disease on mortality in cardiac transplant recipients (from the United Network of Organ Sharing Database)

Peripheral vascular disease (PVD) portends increased morbidity and mortality in patients with heart failure. In those with advanced heart failure, heart transplantation (HT) is the only causative therapy to increase survival. However, little is known about the impact of symptomatic PVD on survival of HT recipients in large multicenter cohorts. The aim of this study was to investigate an association between recipient symptomatic PVD and survival after HT. We analyzed 20,297 patients from the United Network of Organ Sharing data set. Survival analysis using a control cohort established by propensity matching was performed. There was an increased prevalence of traditional cardiovascular risk factors in 711 patients with symptomatic PVD compared with 19,586 patients without PVD. Patients with pretransplant symptomatic PVD had increased post-transplant mortality compared with those without PVD (1-, 5- and 10-year survival rate 91.5% vs 94.9%, 74.8% vs 82.6%, 48.6% vs 54.7%, respectively, log-rank p<0.001). On multivariate analysis based on the propensity matching, factors associated with a lower survival rate were presence of PVD (hazard ratio 1.20, 95% confidential interval 1.02 to 1.42, p=0.030), and female gender (hazard ratio 1.22, 95% confidence interval 1.02 to 1.47, p=0.034). In conclusion, patients with symptomatic PVD have a lower survival rate after HT. Symptomatic PVD should be considered an independent risk factor for poor prognosis in patients undergoing HT evaluation.